Ellialtıoğlu, Süleyman Şinasi
The chemisorption of an oxygen adatom on the (001) surface of a perovskite crystal is examined parametrically. An empirical tight-binding method is used in the calculations. The adatom is assumed to chemisorb in a head-on position to the surface cation and the effects of the following parameters are investigated: the orbital interaction V(p) between adatom and surface cation, the difference DELTAE(d) in the self-energies of a surface cation and a bulk one, and the local perturbation DELTAw0 on the self-energy of the surface cation that participated in the chemisorption bond. As a result of chemisorption the oxygen adatom shares the delocalized surface states of the perovskite, and in addition to that two peaks appear next to the surface states, one below the surface band being a bonding state and one above it, being an antibonding state. The change in chemisorption energy with the adatom-surface interaction strength has been investigated.


Radiative Donor-Acceptor Pair Recombination in Tl2Ga2Se3S Layered Single Crystals
Hasanlı, Nızamı (2013-07-01)
The emission band spectra of Tl2Ga2Se3S layered crystals have been studied in the temperature range of 10-50 K and in the wavelength region of 540-700 nm. A broad photoluminescence band centered at 626 nm (1.98 eV) was observed at T = 10 K. Variation of emission band has been studied as a function of excitation laser intensity in the 0.4-51.5 mW cm(-2) range. The analysis of the spectra reveals that the peak energy position changes with laser excitation intensity (blue shift). This behavior of the emission ...
Atomic and electronic structure of Sr/Si(001)-(2 x 2)
Cakmak, M.; Mete, E.; Ellialtıoğlu, Süleyman Şinasi (Elsevier BV, 2006-09-15)
The adsorption of Sr on the Si(001) surface with the semiantiphase dimer (2 x 2) reconstruction is studied, based upon the ab initio pseudopotential calculations. It is calculated that the sermantiphase dimer (2 x 2) reconstruction (2 dimers per unit cell) is more favorable than the (2 x 1) phase (I dimer per unit cell) by an energy of about 0.24 eV/dimer. Considering the energetically more stable reconstruction, we have assumed four possible locations for 1/4 monolayer (ML) Sr adsorption on this surface: (...
Thermodynamic properties of 1 x MgCl2 xCaCl2 melts
Karakaya, İshak (1986-01-01)
An electrochemical formation cell was used to measure the partial molar thermodynamic properties of MgCl2 in {(1−x)MgCl2 + xCaCl2}(1). The results indicate that the melt is nearly ideal in the Raoultian (or Temkin) sense. A classical-thermodynamics analysis of the results was used to construct the T(x) phase diagram which was found to be in good agreement with the accepted diagram.
PARK, JONGEE; Öztürk, Abdullah (World Scientific Pub Co Pte Lt, 2013-02-01)
Glass-ceramics containing only apatite and wollastonite crystals were produced in the system MgO-CaO-SiO2-P2O5-F by the melt casting process. The bioactivity of the glass-ceramics was determined by immersing the glass-ceramics in a simulated body fluid (SBF) and by assessing the resulting apatite formation on the free surface after various immersion durations. A 12-mu m-thick apatite layer formed on the surface of the glass-ceramic containing only apatite crystals after 20 days immersion in SBF. However, th...
Composition dependence of lattice parameters and band gap energies of thallium based layered mixed crystals
Hasanlı, Nızamı (2015-07-01)
Compositional dependence of lattice parameters and unit cell volumes of TlMeX2-type (Me = Ga or In and X = S or Se) layered mixed crystals with monoclinic structure has been studied by X-ray diffraction technique. It is revealed that the lattice parameters of TlGa1-xInxSe2, TlGa(S1-xSex)(2), TlGa1-xInxS2 and TlIn(Se1-xSx)(2) mixed crystals increase due to the substitution of gallium atoms by indium and sulfur atoms by selenium. Moreover, the absorption edges of these mixed crystals have been investigated th...
Citation Formats
H. KOKTEN and S. Ş. Ellialtıoğlu, “CHEMISORPTION OF A P-ADSORBATE ON PEROVSKITES,” PHYSICA B, pp. 39–44, 1994, Accessed: 00, 2020. [Online]. Available: